The use of powered devices can enhance procedural efficiency and efficacy in the field of dentistry, including endodontic, periodontic, and hygiene procedures. For example, a powered device that provides ultrasonic energy through a treatment tip can result in better cleaning and debridement of hard to reach areas or portions of teeth having a complex geometry in these fields, as well as in oral surgery.
In various situations it can be useful to provide a wired or wireless device for performing a dental or surgical procedure. Devices used in the medical and dental fields such as endodontics, periodontics, hygiene, and other surgical procedures, oral or otherwise, are traditionally performed using hand tools, or externally powered devices. Both are effective, but can have drawbacks. For example, the use of hand tools can result in a lengthier procedure and cause pain, discomfort, or fatigue for the clinician, patient, or both. Powered devices alleviate those problems and can be effective, but can introduce other difficulties. For example, powered devices with cords can be cumbersome to operate because of the fluid connections and cords that add appreciable weight to the device. Further, fluid connections and cords associated with the powered device can be difficult to manipulate during the procedure. During use, care must be taken to avoid tangling of cords, occlusion of fluid pathways, or damage to either.
In the medical field, it can be useful to consider patient safety, time of procedure, and efficacy in the surgical environment when developing new tools and techniques. Like the dental field, powered devices can have advantages over manually powered or unpowered hand tools, including reducing procedure time and providing minimally invasive techniques. However, current powered devices can have drawbacks including insufficient operating life, heavier weight as compared with hand tools, and insufficient available power. Commercially available piezoelectric devices for use in medical and dental procedures can include inefficient drive circuitry that requires higher input power to achieve suitable results. Excess energy is dissipated as heat or other losses, thereby potentially requiring large or higher rated circuit elements, heat sinks and a large device footprint. Previous piezoelectric scaler circuit designs used hard switching and power hungry approaches to force mechanical resonance to occur at a defined electrical signal near the mechanical resonance point. Typically, hard switching was accomplished by connecting a transformer to the piezoceramic which was also connected to “ground.” Such electrical circuits are lossy since the energy from each pulse charges the capacitive piezoceramic load and then the energy is discharged to ground. Examples of circuitry employing hard switching for driving ultrasonic devices can be found in U. S. Pat. Nos. 3,596,206, 3,651,352, 4,445,063, and 4,168,447.
In yet another aspect, some prior cordless devices can be coupled to a source of fluid. In order to provide the fluid to the treatment site, a pump, either remote from, or internal to the device, can be used. Internal electronic pumps draw power away from the power supply, which in the case of a battery power supply can drain the battery more quickly.
The control center for existing devices can be located remotely, in which case the operator of the device can need to continually and simultaneously support the device and adjust the control system, which can add time and require additional assistance to complete the procedure. Also, alternating current (AC) powered devices can require features such as shielding from power line voltages and currents.
These and other problems can also arise during operation of an ultrasonic device. Therefore, there is a need for a handheld ultrasonic device that overcomes the aforementioned drawbacks.